Rowling has said in an interview that the fact that Newt still has a wand after being expelled is 'significant'.

So Why did he get expelled?

 

J.K. Rowling: Well, he took the blame for something someone else did. That's significant, but I can't tell you why.

 

How did he keep a wand?

 

J.K. Rowling: How did he keep a wand? That's also significant, and I can't tell you why.

 

_{Snitchseeker's interview with J.K. Rowling at the world premiere of Fantastic Beasts and Where to Find Them}

Rowling has said in an interview that the fact that Newt still has a wand after being expelled is 'significant'.

So Why did he get expelled?

J.K. Rowling: Well, he took the blame for something someone else did. That's significant, but I can't tell you why.

How did he keep a wand?

J.K. Rowling: How did he keep a wand? That's also significant, and I can't tell you why.

_{Snitchseeker's interview with J.K. Rowling at the world premiere of Fantastic Beasts and Where to Find Them}